Keeping the Lifelines Open

By LISA GUERNSEY

Published: September 20, 2001

ON any given day, Dave Johnson knows far more than most people about the many phone calls that are crisscrossing the United States. Mr. Johnson, a spokesman for AT&T, works in the company's global network operations center in Bedminster, N.J., where he and his colleagues monitor 141 vast projection screens that provide minute-by-minute details on the state of the country's largest long-distance system. By watching computerized maps of the United States, they can tell in an instant whether there are any jams in long-distance traffic.

On an ordinary day, Mr. Johnson said, those maps are blissfully blank, showing no unusual activity. But on Tuesday, Sept. 11, as soon as Mr. Johnson and his colleagues saw the first television reports of the terrorist attacks on New York and Washington, they knew that this would not be an ordinary day.

''We all looked at each other and said, here we go,'' Mr. Johnson said. Within minutes, the screens lighted up, showing tens of millions of calls -- many from worried relatives and friends -- that threatened to clog the system. ''What started as a quite peaceful day,'' he said, ''we instantly knew was not going to be quiet and peaceful any longer.''

In Manhattan, the threat to the phone system was not just traffic -- it was physical damage. The collapse of the World Trade Center crippled many of the connections that downtown Manhattan depended on, threatening crucial links for the police and emergency crews. Cellular sites were knocked out. A switching office for local service was badly damaged by falling debris and burst water pipes. Fiber-optic transport equipment was crushed. Power failures cut off high-speed Internet service for many companies across the city.

By day's end, the telecommunications system in the country and particularly in New York had experienced what was probably the biggest test ever of its ability to withstand a physical attack and a national emergency.

So far, the results are encouraging. Several companies trucked in temporary cellular towers. The 911 system was never disrupted. Long-distance lines were kept open for New Yorkers who were calling out. For most people, the Internet was slowed but intact.

Bruised and battered, the communications infrastructure persevered, but not before providing lessons about how networks adapt to such extreme conditions and what more can be done to preserve them in emergencies.

Verizon had to deal primarily with the effects of sheer destruction. The company's office at 140 West Street was a central switching office for local telephone traffic. Five stories of debris from 7 World Trade Center, which collapsed Tuesday afternoon, fell against the building, which was also hit by a massive steel girder from the North Tower. The basement is flooded with water from shattered pipes, rendering the backup power generators useless.

The loss of all service at 140 West Street left as many as 175,000 customers in the area unable to make or receive calls. It also affected companies that used as many as 3.5 million lines that carry Internet traffic and private financial information through Lower Manhattan. Those lines, Verizon says, were either damaged or were attached to switches that have no power. Several companies had to use alternative communications channels to provide Internet access to their employees or subscribers.

''I suspect every business in Manhattan is in some way affected by the loss of communication,'' said Ivan Seidenberg, co-chief executive of Verizon. ''Lower Manhattan is a pretty influential place in the entire scheme of life.''

Among the companies affected was Earthlink, which was unable to provide high-speed Internet service to more than 7,000 subscribers until Friday. The effect rippled out to Washington, because Earthlink had been channeling some Washington subscribers through the New York center to balance its load. Kevin Brand, the company's vice president for network operations, said that to solve the problem the company rerouted traffic through several points in the Northeast that are controlled by one of its partner companies.

Failures of backup power also hit several other network facilities around downtown Manhattan. AT&T was unable to run telephone-switching equipment in the World Financial Center because of power losses.

Many cables in the area are also in bad shape. When water mains broke after buildings collapsed, the water seeped into cables that have since short-circuited, Verizon officials said. AT&T officials say they are certain that they lost several pieces of sophisticated equipment in the basement of the World Trade Center that were used to transport data over fiber-optic cables.

The phone system's losses were human as well. A half-dozen Verizon workers are assumed to have perished in the trade center's destruction, among them two technicians who were in the North Tower on a maintenance mission. They had called their co-workers to tell them they were escaping to the roof after they realized the extent of the fire caused by the first plane crash.